▎ 摘　　要

NOVELTY - Surface treatment method for reducing secondary electron yield of oxygen-free copper, involves (i) performing first ultrasonic cleaning on oxygen-free copper sheet, using cleaned oxygen-free copper sheet as anode, performing surface electrolysis treatment in copper sulfate solution, and performing second ultrasonic wave on the oxygen-free copper sheet after surface electrolysis treatment cleaning, (ii) preparing stable and dispersed graphene oxide suspension plating solution and copper sulfate plating solution, (iii) performing first electrochemical deposition on the oxygen-free copper flakes treated in step (i) to obtain a graphene oxide coating on the surface of the substrate, and performing second electrochemical deposition to obtain a graphene oxide/copper composite coating on the surface of the substrate, and (iv) placing the substrate in air to dry naturally, and subjecting to atmospheric heat treatment to obtain the reduced graphene oxide/copper composite coating. USE - The surface treatment method for reducing secondary electron yield of oxygen-free copper is used in space vacuum microwave device manufacturing, radar, electronic countermeasure, communication, safety inspection and medical diagnosis applications. ADVANTAGE - The reduction-oxidation graphene-copper composite coating prepared by the method has excellent bonding strength, excellent thermal stability, excellent electronic absorption performance, and can effectively reduce the secondary electronic yield of oxygen-free copper. The method has simple technique, can control the graphene of the oxidized graphene and the thickness of the coating and can be deposited in the small-aperture annular inner wall. The prepared coating is oxidized to stable reducing oxidation graphene heat treatment, coating surface is uniformly distributed and does not fall off in the thermal cycle. Copper as the connecting agent, improves the copper and carbon because there is no chemical bonding, low solid solubility and thermal expansion coefficient is not matched with low bonding strength and the problem of bad combination stability, which can effectively improve the interface bonding state between the plating layer and the substrate DETAILED DESCRIPTION - Surface treatment method for reducing secondary electron yield of oxygen-free copper, involves (i) performing first ultrasonic cleaning on oxygen-free copper sheet, using cleaned oxygen-free copper sheet as anode, performing surface electrolysis treatment in copper sulfate solution, and performing second ultrasonic wave on the oxygen-free copper sheet after surface electrolysis treatment cleaning, (ii) preparing stable and dispersed graphene oxide suspension plating solution and copper sulfate plating solution, (iii) utilizing the stably dispersed graphene oxide suspension plating solution to perform first electrochemical deposition on the oxygen-free copper flakes treated in step (i) to obtain a graphene oxide coating on the surface of the substrate, utilizing the stably dispersed copper sulfate plating solution, and performing second electrochemical deposition on the substrate on which the graphene oxide coating has been deposited to obtain a graphene oxide/copper composite coating on the surface of the substrate, and (iv) placing the substrate on which the graphene oxide/copper composite coating is deposited in air to dry naturally, and subjecting to atmospheric heat treatment to obtain the reduced graphene oxide/copper composite coating.